32 



Were it not for the calcareous axis, without joints, the writer would hardly suspect this 

 species of belonging to the Gorgonellidae. It seems to fit better in the genus Ellisella than 

 in any other, although the practical absence of double clubs is not in accord with the defini- 

 tion adopted for that genus. 



Genus Plumigorgia new genus. 



Colony bearing symmetrically disposed, delicate, pinnately arranged ultimate branchlets, 

 greatly resembling a plumularian hydroid. Calyces minute. Spicules very minute, oval lenticular 

 and disk-shaped forms embedded in a translucent horn-like ccenenchyma from which it is 

 difficult to separate the spicules. 



i. Plumigorgia hydroides new species. (Plate IX, fig. 3, 3 a; Plate XI, fig. 4). 



p 



Stat. 96. Southeast side of Pearl Bank, Sulu Archipelago. 1 5 meters. 

 Stat. 123. North Bay, Biaru Island. 36 27 meters. (Type). 



Colony straggling in form, branches truly pinnate, greatly resembling a plumularian 

 hydroid; total height 13. 7 cm. The colony arises from an irregularly calcareous mass. The main 

 stem is 2 mm. in diameter near its base and forks 2.8 mm. above its origin. The main branches 

 are stiff and tortuous, most of their branchlets being broken off, but their stubs show that they 

 were rather regularly alternate, at least on the distal parts of the colony. The ultimate branchlets 

 are regularly alternate offshoots from the secondary branches, and are gracefully curved exactly 

 as are the hydrocladia in a plumularian. The ultimate twigs are about 3.5 mm. apart and 

 attain a length of 13 mm. The axis in these branchlets is exceedingly attenuated, being at 

 the ends no larger than a hair, and is calcareous throughout. The calyces are all lateral, but 

 are otherwise irregularly disposed, being opposite, subopposite or alternate in different parts 

 of the same twig. 



The individual calyces are very minute for alcyonarians, a typical one being less than 

 .5 mm. in height and about as wide as high. They vary in shape, some being dome-shaped 

 and others in the form of short cylinders. Their walls are full of minute disk-shaped or 

 biscuit-shaped spicules. These are embedded in the ccenenchyma in a peculiar manner, not 

 being contiguous, but distinctly spaced as if stuck in a horn-like translucent ccenenchyma, each 

 spicule being distinctly isolated from its fellows. This horn-like matrix is peculiar in that it 

 resists boiling in a potash solution and comes off from the axis like a transparent pellicle with 

 the spicules still firmly embedded. An end view of a calyx shows that the aperture is very 

 small, when the polyp is retracted, and the margin is surrounded by eight not very strongly 

 marked lobes. The tentacles have very long and slender pinnules and their dorsal surfaces 

 are packed with minute disk-like spicules which are even smaller than those in the calyx walls 

 and ccenenchyma. 



Spicules. These are of two forms which are really but modifications of one. They 

 are all lenticular or disk-shaped. Often the oval is constricted in the middle and thus a biscuit 



